#include <iostream>

int main() {
    int n;
    std::cin >> n;
    int sum = 0;
    for (int i = 0; i < 5; ++i) {
        sum += n % 10;
        n /= 10;
    }
    std::cout << sum << std::endl;
    return 0;
}    
/**************************************************************
	Problem: 1418
	User: fuyijun
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2072 kb
****************************************************************/